The construction and maintenance of interactive user interfaces have been simplified by the development of a generation of software tools. The tools range from window managers, toolkits, and widget sets to user interface management systems and knowledge-based assistants. However, only a small number of the tools attempt to incorporate principles of good design. They offer no help with decisions regarding the variety of input devices and methods available. In this paper we briefly describe a methodology for interaction technique selection based on natural physical analogs of the application tools. Special emphasis is given to the physical characteristics of input devices and the pragmatics of their use. The methodology is incorporated in a software environment named Toto which includes knowledge acquired from a variety of disciplines such as: semiotics, ergonomics, and industrial design. Toto also incorporates a set of interactive tools for modifying the knowledge and for supporting the selection of natural interaction techniques. A two phased design process (matching followed by sequencing) is embedded in the Toto rule base. Examples of the use of Toto tools are provided to illustrate the design process.